The definition of sloth would be laziness, unwillingness to work or act.
Two context clues are the word "idleness" and the phrase "doing of nothing". Idleness may mean boredom, but also dullness. Doing of nothing clearly supports the notion of not working, not acting.
Answer:
C.There is very little rainfall and the temperatures can be extreme.
I would say definitely use your time wisely. Make sure you are fully focused too. Though it may be difficult to focus, (I understand) try and find some outside resources that can help you bring interest into what you're learning in any subject.
